We construct analytically stationary global configurations for both aligned and logarithmic spiral coplanar magnetohydrodynamic (MHD) perturbations in an axisymmetric background MHD disc with a power-law surface mass density Σ0 ∝ r , a coplanar azimuthal magnetic field B0 ∝ r −γ , a consistent self-gravity and a powerlaw rotation curve v0 ∝ r −β where v0 is the linear azimuthal gas rotation spe...

It remains unknown whether or not smooth solutions of the 3D incompressible MHD equations can develop finite-time singularities. One major difficulty is due to the fact that the dissipation given by the Laplacian operator is insufficient to control the nonlinearity and for this reason the 3D MHD equations are sometimes regarded as “supercritical”. This paper presents a global regularity result ...

The Monty Hall Dilemma (MHD) is an intriguing example of the discrepancy between people's intuitions and normative reasoning. This study examines whether the notorious difficulty of the MHD is associated with limitations in working memory resources. Experiment 1 and 2 examined the link between MHD reasoning and working memory capacity. Experiment 3 tested the role of working memory experimental...

Pulsed power technology is used to produce transient MHD-regime plasmas having topology and dynamical behavior similar to solar and astrophysical plasmas. These plasmas are not exact scale models, but exhibit many behaviors similar to actual solar and astrophysical plasmas, for example, coUimation, kinking, and jet motion. These plasmas can also display an interaction between MHD-dynamics and n...

For understanding the structure of an MHD-scale Kelvin-Helmholtz Instability (KHI) in a non-linear stage, we have performed two-dimensional two-fluid simulations including finite electron inertial effects. In the twofluid system, magnetic reconnection occurs spontaneously because the ’frozen-in’ condition can be broken by the electron inertial effects. When an MHD-scale velocity shear exists, a...

The nonlinear dynamics of a bundle of magnetic flux ropes driven by stationary fluid motions at their endpoints is studied, by performing numerical simulations of the magnetohydrodynamic (MHD) equations. The development of MHD turbulence is shown, where the system reaches a state that is characterized by the ratio between the Alfvén time (the time for incompressible MHD waves to travel along th...

The lowest-order description of a magnetized plasma is given by magnetohydrodynamics (MHD). However, many astrophysical plasmas (as well as some laboratory plasmas) are relativistic, in that either the thermal speed or the fluid flow speed approaches the speed of light, and conventional MHD is not consistent with special relativity. Beginning with exact laws of motion, this work derives a gener...

The evolutionary conditions for the dissipative continuous magnetohydrodynamic (MHD) shocks are studied. We modify Hada’s approach in the stability analysis of the MHD shock waves. The matching conditions between perturbed shock structure and asymptotic wave modes shows that all types of the MHD shocks, including the intermediate shocks, are evolutionary and perturbed solutions are uniquely def...

Compressible turbulence, especially the magnetized version of it, traditionally has a bad reputation with researchers. However, recent progress in theoretical understanding of incompressible MHD as well as that in computational capabilities enabled researchers to obtain scaling relations for compressible MHD turbulence. We discuss scalings of Alfven, fast, and slow modes in both magnetically do...

In order to simulate global magnetogydrodynamic phenomena in tokamaks, a new gyrokinetic PIC (particle-in-cell) code, Gpic-MHD, is developed. Gpic-MHD is written in cylindrical geometry and has single-helicity (two-dimensional) version and multi-helicity (three-dimensional) version. The kinetic internal kink mode is successfully simulated and compared with the results of gyro-reduced-MHD (GRM) ...